Dynamic x-ray imaging systems are used for both diagnosis and image-guided procedures in a variety of places, including the human body. For example, x-ray image-guided vascular interventions are carried out by guiding a catheter through the patient's vasculature while a series of images depicting the catheter and the patient's vasculature are displayed to a physician. A primary example of such a procedure used in providing treatment of vascular diseases is a minimally invasive procedure commonly referred to as endovascular image-guided intervention (“EIGI”). EIGIs generally involve the insertion of a catheter into the femoral artery, which is then guided through the patient's vasculature to the site of the pathology to be treated. Fluoroscopic images provided to the physician allow the physician to identify the current position of the catheter tip, as well as how the catheter tip might be guided further through the vasculature. The temporal resolution of existing fluoroscopic systems is quite good, and so the image presented to the physician shows the catheter tip at or very near the actual position of the catheter tip, but the generated images are relatively noisy because of the lower exposure per frame that is often used in an EIGI procedure.
Three images from a longer neurovascular interventional sequence are presented in FIGS. 1, 2 and 3 to provide a better understanding of an EIGI procedure. FIGS. 1, 2 and 3 show different stages of an EIGI procedure conducted to reach an aneurysm. As can be seen from these figures, the acquired images are noisy. Although the image quality may be improved by increasing the radiation per frame, doing so would expose the patient to more radiation for a given procedure. Since images are obtained at a frame rate usually of 7.5 fps to 30 fps during a fluoroscopic procedure, the integral dose to the patient can be substantial. There is a need for a method and system which reduces the integral dose, and yet also reduces the noise in acquired images.